Mathies et al. (U.S. Patent Publication 2004-0209354, Oct. 21, 2004) describes a microfluidic structure comprising: a first surface including a pneumatic channel; a second surface including a fluidic channel; and an elastomer membrane located between the first and second surfaces such that the application of a pressure or a vacuum to the pneumatic channel causes the membrane to deflect to modulate a flow of a fluid in the fluidic channel. Fluid flow in a fluidic conduit of such devices can be regulated by a diaphragm valve in the conduit that comprises a valve seat on which the elastomer membrane sits. When in contact with the seat, the elastomer membrane blocks fluid flow across a fluidic conduit. When out of contact with the seat, a passage exists that allows fluid communication across the valve. Mathies et al. indicates that the device can have surfaces of glass plastic or polymer.
Anderson et al. (Nucleic Acids Res. 2000 June 15:28(12):E60) describes a plastic device held together using ultrasonic welding or adhesives.
Jovanovich et al. (U.S. Patent Publication 2005/0161669, Jul. 28, 2005) describes reducing macroscale sample solutions to microscale volumes, for example by concentrating milliliters to microliters or smaller volumes for introduction into one or more microfluidic devices. The document describes embodiments capable of acting as modular scale interfaces, permitting microscale and/or nanoscale devices to be integrated into fluidic systems that comprise operational modules that operate at larger scale.
Jovanovich et al. (WO 2008/115626, Sep. 25, 2008) describes microfluidic chips made from plastic components. The document also describes integration of macroscale devices such as automation and robotics with nanoscale sample preparation and analysis.